1. Field of the Invention
The present invention relates to an environmentally safe pink lamp which does not contain selenium or cadmium. More particularly, the present invention relates to a pink decorative lamp comprising an electric light source enclosed within a vitreous, light transmissive envelope with a selenium and cadmium free coating comprising a chrome tin pink sphene deposited on the surface of the envelope.
2. Background of the Disclosure
Pink decorative lamps have been made and used for some years and have included pigments such as cadmium selenide and cadmium sulfide in the lamp coating for emitting a pink color. Such lamps generally comprise a glass envelope enclosing a filament within and terminating at one end in a conventional metal screw base, with the interior or exterior surface of the glass envelope containing an inorganic pigment coating which includes cadmium selenide and cadmium sulfide as coating pigments for emitting a pink colored light. Most lamp manufacturers electrostatically apply such coatings as a dry powder to the interior surface of the glass lamp envelope. Electrostatic forces cause the powder to adhere to the interior surface or wall of the glass envelope as disclosed, for example, in U.S. Pat. Nos. 4,441,046; 4,441,047 and 4,597,784, the disclosures of which are incorporated herein by reference. Some decorative lamps have an enamel coating containing such pigments on the exterior surface of the glass envelope. In either case, the coatings must be resistant to the heat generated by operation of the lamp.
Selenium and cadmium containing compounds such as cadmium selenide and cadmium sulfide are regarded as hazardous materials with respect both to workers who are exposed to such materials and also to the environment with respect to disposal of waste containing such compounds. Accordingly, there is a real need to eliminate or at least reduce or minimize the amount of selenium and cadmium present in lamps, including the pink color decorative lamps which employ cadmium and selenium compounds.